Largely?

No.

He was (along with his government) partly responsible. What he did or (didn’t do) wasn’t motivated by racism or imperialism, and it wasn’t much of a crime either.

The famine wasn’t caused by food shortage. It was caused by a complete misunderstanding of its causes

The Brits assumed it was caused by food shortage, and so wasted their time by attempting to measure nonexistent food shortages, trying to fathom how the famine even came to be.

Once they realised there wasn’t a shortage of food, they chose not to ship much (or any) food to Bengal at all, because after all, on paper, there was enough food to feed everyone (and also export to British troops abroad).

What they didn’t realise was that because of wealthy Indian landowners hoarding food, general wartime inflation, and speculative buying, food prices had shot up.

Poor rural peasants in their millions couldn’t afford to buy food, so they starved.

Burma was under Japanese occupation, so no food could be shipped in from around the area.

The British also chose to continue exporting food from India because, again, they didn’t understand that while enough food was there to feed everyone, it was also too expensive for the victims to buy.

This is also why the famine code wasn’t applied- there wasn’t a shortage of food at all (on the contrary, harvests of food crops in Bengal were higher than in previous years), so the British assumed the famine wasn’t much of a famine.

The Viceroy of India (Archibald Wavell) and the Governor of Bengal asked Churchill for (more) food shipments to alleviate the suffering, and he refused to do what they asked him to because a) he was more concerned about feeding his soldiers and about WWII and b) there was, according to him, enough food in Bengal (already) to feed the victims of the famine- and soil that was of sufficiently good quality to grow more. He was right; he just didn’t understand the fact that the food was out of reach, monetarily, for the famine’s victims.

Was Churchill to blame?

Only partly- and his was a small part to play. He didn’t cause the famine. He didn’t even purposefully worsen it. He and his government only misunderstood the cause of the famine. That was the only part they played. Such a famine had quite literally never taken place before, so I don’t blame him for misunderstanding the causes of the famine. As I said, Churchill had little to do with it.

What happened was unfortunate, lamentable, and sad, but it wasn’t Sir Winston Churchill’s handiwork.

TL;DR: The famine was not deliberately caused- it was a terrible mistake; a lamentable misunderstanding. Considering that this famine was one-of-a-kind and that such a famine hadn’t ever taken place before, the British do not deserve all of the blame. Indians did not die because Churchill wanted them to: Indians died because Churchill didn’t know what was going on, and so didn’t know what to do. His efforts to solve the famine and help the Indians were focused on the wrong problem, and so weren’t very effective.